Enner Valencia thought he had put Ecuador in front in the fourth minute with a header from close range after Qatar goalkeeper Saad Al Sheeb was caught out of position.
However, after a lengthy review from the VAR team, Valencia’s goal was ruled out, much to the bemusement of Ecuador’s players.
Fans were also left puzzled as no explanation was given at the time but a subsequent replay showed that Michael Estrada’s foot and knee was marginally offside during the build up.
Felix Torres was the player challenging Qatar’s goalkeeper but the ball fell to Estrada, who headed the ball towards Torres, whose overhead kick across goal was met by Valencia.
Former England striker Alan Shearer criticised the lack of information given to fans about the decision during the half-time break.
‘I don’t think there’s any person in the world who thinks that’s offside,’ Shearer told BBC Sport.
‘The sad thing is you have 60,000 in the stadium, millions around the world and no one had a clue what was going on. No information was being fed back at all. That can’t be right.’
Ecuador were not made to wait much longer for their first goal as Valencia put the South American nation ahead from the penalty spot in the 16th minute.
Valencia then doubled Ecuador’s advantage in the 31st minute with a brilliant header.
Meanwhile, Senegal play Netherlands in the second game in Group A on Monday.
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